Apparatus for burning pulverized coal



March 10, s JACQUES 1,795,951

APPARATUS FOR BURNING PULVERIZED COAL Filed July so; 1925 v V QINVENTORWv-W ATTORNEY} atented Mar. 10, 1931 UNITED STATES PATENT F K I I Y.

STANLEY A. JACQUES, or CHICAGO, ILLINoIs ss'IGNo TO INTERNATIONAL com-BUSTION ENGINEERING QORPORATION, A CORPORATION on DELAWARE .APIBARATUSFOR BURNING PULVERIZED COAL Application filed July 30,

. This invention relates to the art of burning pulverized coal and isparticularly useful in the burning of finely divided fuel understationary boilers.

In many forms of apparatus for the burning of pulverized coal understatlonary bo1lers, the fuel is admitted thru a plurality of burnersarranged in a row. The installations are operated at all ratings frompurely nom- 1o inal loads to maximum or peak loads, the

amount of coal being burned at any particular time being dependent uponthe rating at which the installation is then being operated. To meetthis condition'it has been customary to cut out one or more burners orto increase the number of burners which are supplying coal as the casemay be No difficulty 1s encountered when all of the burners are feedingcoal. However, it is quite difficult to secure a balanced flame when.cutting out one or more burners, the disposition of the burners inpresent standard practice being such that an unbalanced flame conditionarises by virtue of the fact that more coal will be admitted 1n onepartof the combustion chamber-than in an-v Fig. l'is a diagrammaticpartial front elevation of a boiler and furnace setting equipped with myimprovements;

Figs. 2, 3 and 4; inclusive illustrate how the invention may be put intoeffect with the arrangement shown in Fig. 1 p

Fig. 5 shows a modified arrangement for 5 carrying out my invention; and

.to the furnace by means of a pipe or pipeslO,

nozzles are burnercastings 14: thru which ad- 1925. Serial No. 46,991.

F ig. 6 shows another modification applicable where direct firing isdesired. Referring now to F ig. 1 the reference character A indicatesacombustio'n chamber which has an outlet towards the rearof the arch "orroof 7, thru which the products of combustion pass-upwardly to theboiler 8, which may be of any conventional design.

The front wall of the combustion chamber is provided with a plurality ofair inlets 9 thru which air may be admitted for combustion, under controi i I The coal preferably with'carrying air, is conducted from asuitable source of supply in this case but one pipe being shown. Thispipe '10 branches, in the present showing there being three branches 11.Each of the branches is controlled by a damper, or other suitablecontrol device 12. Y

Secured to each pipeis a burner nozzle 13, these burner nozzles changingfrom a circular crosssection to a flat elongated cross section. 'Theburner nozzles are, therefore, of the fish-tail type. Surrounding the"burner ditional air for combustion may beadmitted. Referring now toFig.'1 it will be seen that the middle nozzle'l3 is located centrally ofthe arch ,7 and discharges downwardly with'the long dimension incross-section of the sheet of fuel delivered thereby parallel to thefront wall. The two outer? burners are set at right angles to the middlenozzle. a The manner in which the arrangement is operated to securesubstantially balanced flame conditions is diagrammaticallyindicatedinFigs. 2, 3 and 4. At low. ratings fuel would only be supplied thru themiddle nozzle as shown in Fig. 2. At an intermediate rating the powderedcoal would be supplied. thru the outer burners and the middle burnerwould be cut out as indicated in Fig. 3. At go maximum rating all threeburners would be supplying coal as indicated in Fig. 4.

It is customary to set the burners alike, that is they would all bedisposed as is the central burner or they would all be disposed as arethe outer burners of Fig. 1. It now, with either arrangement, a burneror burners are cut in or cut out to meet the opera ing conditionsdescribed, it will be seen that it will be diihcult to obtaina balancedflame condition. With the alternate arrangement of the burners a muchmore nearly uniform flame condition will result under all operatingconditions.

In Fig. 5, I have illustrated an elaboration or development of thearrangement to take care of a larger furnace. the central burner may beused alone for very low ratings, or that the two burners on either sideof the central burner may alone be used; or that the middle and the twoend burners may be used; with the production ofsubstanti'ally uniform orbalanced flame conditions within the combustion chamber. The inlets 9are suitably controlled by dampers, so that these may be cut in and cutout as the occasion may demand.

The disposition of the burners alternately at right angles to oneanother, is one that lends-itself particularly well to the purposes ofthe invention. The independent control of the auxiliary air inlets alsomakes it pos sible to secure proper air admission for the various firingconditions described.

InFig. 6 I have illustrated a modification which is applicable when itis desired to have a direct fired pulverized coal burning instal lation,i. acne in which the burners are fed with fuel directly from thepulverizer. In this case the burners are supplied by two mills, mill 15supplying the fuel through pipe 17 and branch pipes 18 to the outsideburn ers, and mill 16, which is preferably of smaller capacity,supplying the fuel to the middle burner through pipe 19.

In this construction mill 15 would be shut down at low ratings the fuelbeing supplied to the middle nozzle only by mill 16. At intermediateratings mill 16 wouldbe shut down and the two end burners would be supplied by 'mill 15. At high ratings both mills and all burners would beused.

This arrangement could also be applied to the construction of Fig. 5,alternate burners being supplied by the same mill,'the larger millsupplying the outside and middle burners and the smaller mill supplyingthe other two.

I claim:

1. In combination, a combustion chamber and means for admitting sheetsof finely divided' fuel and air thereto comprising a row ofindependently controlled burners delivering substantially in the samedirection and having delivery ends elongated in cross-sec- It will beseen that.

tion and alternately set substantially at right angles to each other.

2. In combination, a combustion chamber and means for admitting sheetsof finely divided fuel and air thereto comprising a row of independentlycontrolled burners alternately set substantially at right angles to eachother with the middle burner set to deliver a sheet substantiallyparallel with theiront wall.

In combination, a combustion chamber andineans for admitting sheets offinely divided fuel and air thereto comprising a row of burnersdelivering substantially in the same direction and having delivery endselongated in cross-section and alternately set approximately at rightangles to each other.

at. In combination, a combustion chamber and means for admitting sheetsof finely divided fuel and air thereto comprising a row of burnershaving delivery ends elongated in cross-section and alternately setapproximately-at right angles to each other and delivering the fueldownwardly-into the combustion chamber. y 7

5. In combination, a combustion chamber and means for admitting sheetsof finely dividediuel and air thereto comprising a row of burnersalternately set approximately at ri ht angles to each other anddelivering the fuel downwardly into the combustion chamber adjacent anupright wall thereof, together with means for admitting air at aplurality of points through such wall;

6. In combination, a'combustion chamber, a row of finely divided fuelburners deliver ing in one general direction and having flat nozzles setalternately cross-wise to each other, said burners having independentcontrolling means so that burners may be. out in or out, a'plurality ofair inlets adapted to supply combustion air up to maximum demands andpositioned to deliver air adjacent the streams of fuel from the burners,and control means whereby inlets'may be cut in or out as burners are cutin or out.

7 1. Apparatus for the burning of pulverized coal comprising acombustion chamber, and

plurality of i'uel'and air delivery. burners directed thereinto in thesamegeneraldirection, said burners having delivery e11ds.elon gatedin'cross-section, the longer axes of the delivery ends of alternateburners being set cross-wise with relation to the longer axes of thedelivery ends of the other burners.

8. Apparatus for the burning of pulverized coal comprising a combustionchamber, and a plurality of fuel and air delivery burners directedthereinto in the same general ,direction, said burners having deliveryends elo'ngatedin cross-section, the longer axes of the delivery ends ofalternate burners being set cross-wise with relation to the longer axesof the delivery ends of the other burners, together with independentlyoperablefueI-delivery means to each set of alternate burners.

9. Apparatus for the burning of pulverized coal comprising a combustionchamber, and a plurality of fuel and air delivery burners directedthereinto in the same general direction, said burners having deliveryends elongated in cross-section, the longer axes of the delivery ends ofalternate burners be- 7 ing set cross-wise with relation to the longer10 axes of the delivery ends of the other burners,

together With independently operable fueldelivery means to each burner.A

In testimony whereof,' I have hereunto signed my name.

I STANLEY A. J AOQUES.

